Birmingham centre-back Matthew Upson concedes he faces a battle to be fit for Saturday's relegation showdown with rock-bottom Sunderland.
Manager Steve Bruce has been without Upson for almost three weeks due to a groin injury sustained in a 2-0 defeat to Arsenal at St Andrews.
Upson is part of a City treatment room bursting at the seams as Bruce was without 11 first-team players for Sunday's 1-0 FA Cup fifth-round win at Stoke.
Although Bruce's son Alex and on-loan Czech defender Martin Latka performed well at the heart of the defence at the Britannia Stadium, there is no substitute for experience.
In a must-win home clash with Sunderland, Upson's presence would be crucial, although he is unsure over his availability.
'I couldn't honestly answer whether or not I am going to play,' said Upson, speaking at the launch of the first Football Association-accredited Online Course Provider at Solihull College.
'I am optimistic I will be involved as I did some running yesterday and I need to see how it reacts.
'If it reacts kindly then I can push on for Saturday. If not, I have to take a step back, get home, put my feet up and get the ice on it.
'It is recovering. I had a bit of a blocked pelvis, which related into muscle soreness. It isn't a big issue, though, as I just need it to settle down.'